This invention relates to a working machine of the kind including a chassis, a ground engaging propulsion structure, and a working arm. Such machines are used to perform for loading and/or excavating operations, in the former case the working arm being a loader arm and in the latter case there being also a working arm being an excavating arm, or a single excavating working arm.
The chassis of such working machines typically includes a pair of chassis members which extend substantially longitudinally of the machine and the chassis members being interconnected by cross members, the longitudinally extending chassis members and the cross members together providing the main structural support for components such as axles carrying wheels, the working arm, an engine and a cab structure, and provide resistance to torsional deformation of the machine between the front and rear ends. It will be appreciated that the components themselves may add rigidity to the machine and may make some contribution to torsional stiffness.
Machines are also known in which a chassis is provided by a single central longitudinal extending chassis spine, with a cab mounted on one side of the spine and the engine on the other side of the spine.
More particularly but not exclusively the invention has been devised for a working machine for performing loading operations. It is desirable for some applications, for such a working machine to have a minimal height, for example so that the machine may work within a standard container space, within a silo or otherwise where height is particularly restricted. However it is also desirable for there to be a minimum clearance between the chassis and the ground to enable the working machine to be driven over rough ground. These two requirements compete and ordinarily, any working machine design has to be a compromise between these requirements.